need help with calculations for my chemistry lab! (Classic Titration 1 Lab) first picture is the data table that was gathered during the lab in which will be used to do the calculations.second picture explains the intro, purpose, and the procedure of the whole lab as a reference if the data table or the whole thing does not make sense. I'd really appreciate it if I could get help on the calculations. Thank you! Sample # Final buret reading, mL | Initial buret reading, mL| Volume NaOH used, mL10.48.4 mL8.5 mL8.5 mL118.82323.441.214.932.70.125 M NaOHCalculations (Show all work)1. a. Calculate the number of moles of sodium hydroxide used for each titration.b.Calculate the number of moles of hydrochloric acid present in each sample.c.Calculate the concentration of the hydrochloric acid in each sample.d.Calculate an average for the three samples. IntroductionOne of the most common problems dealt with bychemists is to determine how much of something ispresent in a sample. If the sample contains acid orbase, the determination of amount is usually determinedby titration. Acid-base titrations can be used tomeasure the concentration of an acid or base in solutionProcedure1)solution into a beaker; record the exact molarity in yourdata table and label the beaker.Measure out 75 mL standard sodium hydroxideClamp a clean 50 mL buret to a ring stand. Use2)a funnel to pour solution into buret; rinse the buret threetimes with 5 mL standard sodium hydroxide; discardthe rinsate.and to calculate the molar mass of an unknown acid orbase.Titration is a method of volumetric analysis – the use ofvolumetric measurements to analyze an unknown. Inacid base chemistry, titration is most often used toanalyze the amount of acid or base in a sample orsolution. Consider a solution containing an unknownamount of hydrochloric acid. In a titration experiment,a known volume of the hydrochloric acid solutionwould be titrated by slowly adding a standard solutionof a strong base such as sodium hydroxide. The titrant,(the base in this case) reacts with and consumes theacid via a neutralization reaction. The exact volume ofUse a funnel and fill the buret to above the zero3)mark with sodium hydroxide solution. Open thestopcock and tap the buret gently to allow air bubbles toescape from the tip; this should require no more than2-3 mL sodium hydroxide solution.4)data table. NOTE – volumes are read from the topdown in a buret; always read from the bottom of themeniscus, and remember to include the appropriatesignificant figures.5)Record the initial volume of the buret in yourbase needed to react completely with the acid ismeasured. This is called the equivalence point of thetitration – the point at which stoichiometric amounts ofacid and base have been combined.Using a pipet, transfer 10.0 mL unknownhydrochloric acid solution to a 125 mL Erlenmeyerflask. Add approx. 20 mL distilled water with swirling;add three drops phenolphthalein indicator withswirling.6)tip of the buret is inside the mouth of the flask. Place apiece of white paper under the flask to make it easier todetect the color change of the indicator at the endpoint.7)of the sodium hydroxide solution to flow into the flaskwhile continuously swirling the flask. Observe thecolor change that occurs.8)Knowing the exact concentration and volume of thetitrant gives the number of moles of sodium hydroxide.The latter, in turn, is related by stoichiometry to thenumber of moles of hydrochloric acid present in theunknown.Position the flask under the buret such that theIndicators are usually added to acid-base titrations todetect the equivalence, or end point. The end point isthe point at which the indicator changes color andsignals that the equivalence point has been reached.For example, in the HCl/ NaOH titration describedabove, the pH of the solution is acidic before theequivalence point, and basic afterwards. A pH ofexactly 7 corresponds to the neutral products, water andsodium chloride.Open the stopcock to allow approximately 5 mLContinue to add sodium hydroxide slowly, in0.5 mL increments, while swirling the flask. Use awash bottle to rinse the sides of the flask.The progress of a titration can be followed bymeasuring the pH of the solution being analyzed as afunction of the volume of titrant added. A plot of theresulting data is called a pH or titration curve. Titrationcurves allow a precise determination of the end pointwithout using an indicator.9)for 30 or more seconds with swirling, the endpoint hasbeen reached. Close the stopcock and record the finalburet reading for Run 1 in your data table.10)flask with a few mL distilled water.When the first faint pink appears, and remainsPour the solution out of the flask and rinse thePurposeThe purpose of this experiment is to become familiarwith the titration process, in order to determine theconcentration of an unknown hydrochloric acidsolution.11)Repeat steps 4-10 with a second 10.0 mLsample of hydrochloric acid.12)Repeat steps 4-10 with a third 10.0 mL sampleof hydrochloric acid.

mole of NaOH used can be determined using law of chemical equivalence.

Answered: Sample # Volume NaOH used, mL Final…

8th Edition

ISBN:9781285644561

Author:Seager

Publisher:Seager

Chapter9: Acids, Bases, And Salts

Section: Chapter Questions

Problem 9.103E